Treatment Practice of Wastewater from Surface Finishing Processes of Diesel Engine

Production sections of a diesel engine heavy industry enterprise generated surface finishing wastewater.Cr6+ in chromium wastewater was reduced by sodium sulfite,and cyanide in cyanide wastewater was removed by alkaline chlorination process.The treated wastewater was mixed with acid-alkali wastewater for coagulation,sedimentation and filtration.The treated effluent quality met the first class criteria specified in the Integrated Wastewater Discharge Standard(GB 8978-1996) and Emission Standard of Pollutants for Electroplating(GB 21900-2008).The process flow,design parameters and device configuration were introduced,and the design features,operation costs,and system commissioning operation were summarized for reference in similar projects.